In my prior U.S. Pat. No. 3,831,862, I disclosed a spray tip assembly in which the spray tip orifice is mounted in a removable and reversible sleeve which is secured to the housing with a sliding pin interlock. This construction requires loosening of the body from its adapter to reverse and/or replace the spray tip orifice.
In my prior U.S. Pat. No. 4,116,386, I disclosed a spray tip assembly in which the spray tip orifice is mounted in a cylindrical turret member which can be rotated in the housing to reverse the orifice member for cleaning. This construction employs a solid, resilient plastic seal which has a cylindrical surface of the turret member.
A recently issued U.S. Pat. No. 4,165,836, discloses that solid plastic seals experience excessive wear and suggest that an entirely metal seal be used to provide metal-to-metal contact between the seal and turret member. Experience with devices of this invention, however, reveals that the metal seal is not effective with low viscosity liquids which leak from the assembly under the high pressures used in airless spraying, and in my parent, copending application. I disclose that this difficulty can be avoided by using a thin layer Teflon seal on a metal seal support.
In a typical spray application, it is frequently necessary to substitute different size orifice members, and this requires interchanging the turret member. Heretofore, the various seals and seal supports dislodged from the spray tips when the turret members were removed, complicating reassembly. It is desirable that the spray tip permit a simple removal and interchanging of the spray orifice without disassembly and without dislodgement of the other parts of the spray tip.